Merge remote-tracking branch 'origin/1.7' into 1.8

CMakeLists.txt

cmake/luajit.cmake

extra/dist/tarantool@.service.in

extra/dist/tarantoolctl.in

extra/exports

extra/luarocks/site_config.lua.cmake

src/CMakeLists.txt

src/backtrace.cc

src/box/CMakeLists.txt

src/box/alter.cc

src/box/applier.cc

src/box/bootstrap.snap

src/box/box.cc

src/box/box.h

src/box/call.cc

src/box/call.h

src/box/engine.cc

src/box/engine.h

src/box/errcode.h

src/box/error.cc